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No pre-start oil pressure

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Auklet

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Cummins marine 6BT 5.9. With ignition on before starting, oil pressure gauge wiggles at 0 psi and low-pressure alarm stays on. Upon starting there is a 5+ (?) second delay before pressure goes to 60 and alarm goes off. Has anyone else had this issue? What should I look to as a cause for this?
 
Auklet said:
Cummins marine 6BT 5.9. With ignition on before starting, oil pressure gauge wiggles at 0 psi and low-pressure alarm stays on. Upon starting there is a 5+ (?) second delay before pressure goes to 60 and alarm goes off. Has anyone else had this issue? What should I look to as a cause for this?
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It's 210hp. I assume these engines are supposed to show at least 30 psi pressure before starting to ensure there is adequate lubrication for start-up. Could anyone confirm this?
 
With the 210 hp Cummins 6BT 5.9, I wouldn't assume it needs to show 30 psi before starting. When the engine is stopped, the oil pressure gauge will normally read zero because the oil pump isn't turning. What matters is how quickly the pressure builds after starting and whether it meets Cummins' specifications for that engine.

I'd first verify the actual pressure with a mechanical gauge rather than relying only on the dashboard reading. If it takes several seconds to build pressure, check the oil level, filter, and possible oil drain-back issues. If the delay is confirmed, have the lubrication system checked before continuing to run the engine.

Triad Diagnostic Solutions provides diagnostic equipment for marine technicians, but in this case, confirming actual oil pressure and following the engine-specific service manual are the key first steps.
 
Thanks. Very helpful. I’ll follow up with your suggestions. Since posting I had a mechanic in to service injectors. His opinion was that the starting oil pressure was normal and commented that most engine wear occurs at start up; it is possible to install an oil primer but few bother with it.
 
Agree, all motors take time to build oil pressure. Only motor I found (I'm sure there are others) that required oil build first before starting was the old Caterpillar dozer and loaders. I have a 955L and it waited for oil pressure to build during cranking before it would let you open the throttle.
 
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